British Prime Minister David Cameron, hoping to defuse controversy over profiting from his late father's offshore funds, took the unusual step Sunday of releasing a summary of the last six years of his tax returns, but lucrative gifts from his mother immediately drew new attention.

The three-page summary of the British leader's earnings and tax payments showed that his mother, Mary Cameron, gave him two gifts totaling about $320,000 in 2011, a year after Cameron's father, Ian, a millionaire stockbroker, died.

The gifts were tax-free and only become taxable if she dies before 2018, leaving British media to question the tax implications.

Newspaper report

The Mail newspaper on Sunday headlined its story on Cameron's financial affairs, "Cameron Tax Bill Dodge."

A Cameron spokesman said the gifts were merely an attempt by his mother to "balance" the inheritance sums received by Cameron and his three siblings after their father's death.

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Cameron released the information after days of muddled answers from 10 Downing Street about his involvement in his father's offshore accounts revealed in the Panama Papers, part of the more than 11 million documents about offshore companies leaked from the Panamanian law firm Mossack Fonseca that were disclosed a week ago by the Washington-based International Consortium of Investigative Journalists.

Before releasing the tax summary, Cameron said Saturday, "I could have handled this better. I know there are lessons to learn, and I will learn them. And don't blame No. 10 Downing Street or nameless advisers. Blame me."

Cameron's financial disclosures showed that he and his wife, Samantha Cameron, each earned about $15,000 in profits from the 2010 sale of their investments in Blairmore Holdings, the offshore company created by his father, Ian. But the earnings were low enough that neither was required to pay capital tax on the gains.

Financial documents

The documents also showed that in the 2014-2015 financial year, the British leader had taxable income of about $283,000 and paid more than $107,000 in taxes.

The disclosures by Cameron, the leader of Britain's Conservative party, failed to quiet opposition attacks on his handling of the information revealed in the disclosures from the Panamanian law firm.

"The prime minister has been forced to admit that not only had he benefited from a company that paid no tax in 30 years, but that he may pay no tax on any benefits potentially gained from the same company," a Labor Party spokesman said. "David Cameron can't hide any more. He needs to come to parliament on Monday and put the record straight."